/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.classfile.attribute.preverification;

import proguard.classfile.*;
import proguard.classfile.attribute.*;
import proguard.classfile.attribute.preverification.visitor.StackMapFrameVisitor;
import proguard.classfile.attribute.visitor.AttributeVisitor;

/**
 * This Attribute represents a stack map table attribute.
 *
 * @author Eric Lafortune
 */
public class StackMapTableAttribute extends Attribute {
    public int u2stackMapFramesCount;
    public StackMapFrame[] stackMapFrames;

    /**
     * Creates an uninitialized StackMapTableAttribute.
     */
    public StackMapTableAttribute() {}

    /**
     * Creates a StackMapTableAttribute with the given stack map frames.
     */
    public StackMapTableAttribute(StackMapFrame[] stackMapFrames) {
        this(stackMapFrames.length, stackMapFrames);
    }

    /**
     * Creates a StackMapTableAttribute with the given stack map frames.
     */
    public StackMapTableAttribute(int stackMapFramesCount, StackMapFrame[] stackMapFrames) {
        this.u2stackMapFramesCount = stackMapFramesCount;
        this.stackMapFrames = stackMapFrames;
    }

    // Implementations for Attribute.

    public void accept(Clazz clazz, Method method, CodeAttribute codeAttribute, AttributeVisitor attributeVisitor) {
        attributeVisitor.visitStackMapTableAttribute(clazz, method, codeAttribute, this);
    }

    /**
     * Applies the given stack map frame visitor to all stack map frames.
     */
    public void stackMapFramesAccept(Clazz clazz, Method method, CodeAttribute codeAttribute,
        StackMapFrameVisitor stackMapFrameVisitor) {
        int offset = 0;

        for (int index = 0; index < u2stackMapFramesCount; index++) {
            StackMapFrame stackMapFrame = stackMapFrames[index];

            // Note that the byte code offset is computed differently for the
            // first stack map frame.
            offset += stackMapFrame.getOffsetDelta() + (index == 0 ? 0 : 1);

            stackMapFrame.accept(clazz, method, codeAttribute, offset, stackMapFrameVisitor);
        }
    }
}
